Sash windows disposed within a master frame are quite common. Generally, the master frame includes a pair of opposed vertical guide rails, an upper horizontal member or header, and a lower horizontal member or base. The guide rails are designed to slidingly guide at least one sash window within the master frame. Double hung sash windows have an upper sash window and a lower sash window. The guide rails of the master frame define an elongated channel. To counterbalance the sash window during movement of the window, a spring balance assembly is affixed to the master frame in the elongated channel and connected to the sash window.
One conventional balance assembly includes a plate, one or more coil springs, and a pivot brake assembly or brake shoe. The plate rotatably supports both coil springs. Each spring has a coiled portion and a free portion. Typically, the free portions of the springs are linear and include an aperture. The pivot brake assembly includes a housing having at least one aperture adapted to receive a fastener. When the conventional spring brake assembly is in the assembled position, the springs are secured to the pivot brake assembly by the fastener. Thus, the free portions of the springs are attached to the housing of the pivot brake assembly by a fastener passing through the aperture in the free portion of the springs and into the aperture of the housing.
Conventional balance assemblies exhibit limitations due to the manner in which the coil springs are connected to the pivot brake assembly. The use of a fastener, including a threaded fastener, requires additional labor and time during assembly of the spring balance. Furthermore, the fastener represents an additional part that increases material costs. In addition, use of the fastener necessitates the extra manufacturing step of forming the aperture in the free portion of the coil spring as well as the corresponding apertures in the housing.
Therefore, there is a tangible need for a spring balance assembly that does not require a fastener to secure the coil spring to the pivot brake assembly, thereby decreasing assembly time and material costs.
The present invention is provided to solve these and other deficiencies.